Calming figures: The numbers that maintain harmony around us

The golden ratio

The most beautiful number ever?

YOU have probably heard of the Fibonacci sequence, that list of numbers where the next digit is given by adding the previous two. It goes 1, 1, 2, 3, 5, 8, 13 and so on. But here’s something strange: work out the ratio of each number and its predecessor, and you start edging towards a specific number. Its first few digits are 1.618.

This mysterious beast is the golden ratio, and it crops up a lot. Try drawing a diagonal line connecting two vertices of a regular pentagon. Divide the length of that line by the length of the pentagon’s sides and there it is. Something similar is possible with an equilateral triangle.

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It turns out to be a quirk of maths. Imagine you have a number, A, and a larger one, B. If you set the numbers so that the ratio of B to A is the same as A + B to B, then that ratio is always the golden ratio.

That might have been the end of the matter, but the ratio has taken on a life of its own. Search for it online and you’ll be inundated with claims that ancient Greek architecture or the human face exhibit such proportions, and that people find it immensely aesthetically pleasing.

The truth is murkier. The human body has countless different proportions, and some of them seem to be close to …